Centrifugal pump



Aug. 18, 1936.

R. H. FREDERICK CENTRIFUGAL PUMP Filed NOV. 20; 1935 3 Sheets-Sheet l Ziu; Di TCLEfjffL/fifl 4 60 -0;

Aug. 18, 1936. R, FREDER|K 2,051,080

CENTRIFUGAL PUMP Filed Nov. 20, 1935 3 Sheets-Sheet 2 Aug l8,'1936. R. H. FREDERICK 2,051,080

C-ENTRIFUGAL PUMP Filed Nov. 20, 1935 4 3 Sheets-Sheet s u u a n-a+u fig Patented Aug. 18, 1936 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to centrifugal pumps, and its object is to provide a pump of simple and efficient construction and operation whereby high pressures and a wide range of capacities,

5 can be attained, and whereby also the priming of the pump can be expeditiously effected.

With this and other objects in view my invention comprises novel features of construction and organizations of parts which, in an exemplifying form, will be hereinafter described, the scope of the invention being expressed in the appended claims.

In the drawings Figure 1 is a longitudinal vertical section of a pump embodying the principle of my invention.

Fig. 2 is an edge view of the circular structure in which-the impeller is mounted.

Fig. 3 is a transverse vertical section of the pump, as on the line 3-3 of Fig. 1.

Fig. 4 is a horizontal section through the pump casing, as on the line 4-4 of Fig. 3, showing the walls of the impeller chamber in sectional plan.

Fig. 5 is a transverse vertical section of the pump in a plane adjacent one face of the impeller, as on the line 55 of Fig. 1.

Fig. 6 is a development of the circumferential vanes of the impeller, and also of the suction and discharge conduits in the respective discal walls of the circular structure in which the impeller is mounted.

Fig. 7 is a partial face development of. the impeller vanes and the spacer ring for the said discal walls.

Figs. 8 to 10,- inclusive, are fragmentary sections througlif'fthe impeller and the conduits of the discal walls, as on the lines 8-8; 9-9 and |l0, respectively, of Fig. 6.

Referring to the drawings, I0 designates a hollow casing having end heads II and I2, the former being integral with and the latter being bolted to the casing. The interior of the easing is generally cylindrical and is divided into two chambers I3 and I 4 by a circular structure which is supported within the casing midway between the two end heads. The chamber I3 is hereinafter termed a suction chamber, and the chamber 14 a discharge chamber. The top of the easing is formed with an inlet l and an outlet IS in direct communication with the respective cham- 50 bers.

The circular structure comprises two discal members l1 and i8 having their peripheries snugly seated against the interior wall of the casing, and being maintained in spaced parallel relation by a spacer ring is interposed therebetween at the wall of. the casing An axial I screw 20 mounted in the end head I! and engaging a boss 2| on the member l8 maintains the associated discal members and the spacer ring in close relation and the inner member I! abutting a suitably-disposed annular shoulder 22 on the inner wall of the casing.

Mounted to rotate within the chamber formed between the spaced members H and I8 is an impeller 23 having spaced peripheral vanes 24 which traverse the continuous annular channel 25 bounding the periphery of the impeller, the radial edges of-each of the vanes being preferably tapered, as at 26, reversely of the direction of rotation of the impeller. The impeller is carried by a motor shaft extension 21, the motor 28 therefor being conveniently bolted'to an integral end extension 280 of the pump casing.

In the present instance the-impeller has on one side thereof. an elongated central hub 29 through which the shaft 21 extends and to which the shaft is splined; the outer end of the hub being secured to the shaft by means such, for example, as the screw coupling 30. The hub is rotatably mountedin an axial bearing 3| formed on the head I l which hub has preferably shrunk thereon a hard metal bushing 32 which, rotating within the packing 33 in the bearing, prevents undue wear of the impeller hub. The bearing extends in close relation to the discal member ll and affords a backer to which such member is pinned or otherwise secured.

The discal members I] and [8 have formed therein reversely-disposed passages 34 and 35, respectively, which are concentric with extended portions of the respective sides of the impeller channel '25 and are in open communication throughout their length with such portions of the channel. The impeller vanes have a close running fit with the surfaces of the members ll and I8, excepting at the extended portions of the channel 25 which are in lateral communication with the respective passages 34 and 35. The passage 34 constitutes a suction conduit leading from the suction chamber l3 to one side of the impeller channel, and the passage 35 constitutes a discharge conduit leading from the impeller channel to the discharge chamber I 4. As illustrated the passages are of substantially uniform crosssectional area, except at their upper and lower ends, it being noted that the upper ends of the passages are expanded or of funnel-like formation, as indicated at 36, and that their lower ends are formed to present inclined or wedge-like wall portions 31 converging from a to b in proximity to the respective sides of the spacer ring I9. The lower portion of the discharge conduit 35 is preferably provided with an outwardly extending drain pipe 38.

The inner peripheral surface of the spacer ring is interrupted at its lower and upper portions by sealing projections 38 and 40, respectively, which are concentric with, and are shaped to ensure a close running fit for the peripheral edges of the impeller vanes, as seen in Fig. 5. The lower projection 39 is co-extensive in length, or substantially so, with that of each of the constricted lower portions of the two conduits 34 and 35, and the upper projection 40 is located in the'portion of the impeller channel between the open upper ends of the respective conduits 34 and 35. Thus it will be seen that during the rapid rotation of the impeller, the lower projection 39 seals the outer ends of the spaces between the successive vanes as they pass between the lower restricted openings of the lateral conduits 34 and 35, and that, in consequence, when the chamber I3 is supplied with liquid through the inlet I5 the liquid is caused to flow under pressure through the conduit 34 and the adjacent communicating portion of the impeller channel until the liquid reaches the restricted portion 31 of the conduit 34, which confined liquid by the actuation of the rapidly rotating impeller vanes thereon is forced across the portion of the impeller channel above the sealing projection 39 and between the adjacent impeller vanes in a manner to enter the lower end of the discharge conduit 35; passing thence to the upper end of the latter and into the discharge chamber l4, and, finally, being ejected through the outlet is from such chamber. It will also be seen that the upper projection 40 by virtue of its formation and location in respect to the impeller vanes serves as an efllcient seal which restricts the return flow of the liquid from the discharge to the suction side of the pump under normal working conditions.

The operation of the hereinbefore described pump is briefly as follows: The liquid flows through the inlet l5 into the suction chamber l3; thence entering the conduit 34 through the open or funnel-shaped end thereof and flowing into the adjacent portion of the impeller channel wherein the rapidly rotating impeller vanes 24 subject the liquid to centrifugal and high velocity force. The liquid is impelled in and constrained to a spiral course in its progress through the associated conduit 34 and the impeller channel 15, as indicated by the dotted sinuous lines in Fig. 7, this course resulting from the greater pressure of the impelled liquid at the outer portion of each succeeding vane than at the'base thereof, as indicated by the dotted lines in Fig. 9. As the liquid courses spirally through the conduit 34 and the associated portion of the impeller channel the pressure at each succeeding turn of the liquid between the impeller vanes is progressively increased until the liquid reaches the constricted lower portion of the conduit, which portion effects a still greater pressure of the liquid, whereupon such liquid, passing through the vane spaces above the seal 39 and across the adjacent portion of the impeller channel, enters the lower portion of the discharge conduit 35 in the discal member 18. The liquid thus delivered under high pressure to the conduit 35 is therein subjected to the same centrifugal and velocity forces by the rapidly rotating impeller vanes as were performed in the conduit 34, thus increasing the pressure force of the liquid to twice that which was developed in the conduit 34 in the passage of the liquid to the point a of that conduit. The conduit 35 delivers the liquid under high pressure and velocity into the discharge chamber 14, whence it is finally ejected through the outlet IS as previously mentioned.

It is to be noted that the described arrangement of the conduits 34 and 35 in relation to the opposite sides of the impeller, and their extended lateral communication with each other transversely of the impeller channel, effect and maintain a smooth and uninterrupted flow of the liquid in the direction of rotation of the impeller, from the suction chamber to the discharge chamber, thus contributing to the practical eiiiciency of the pump.

The priming of the pump can be eiliciently accomplished as follows: At the outset both suc-v tion and discharge chambers l3 and i4, respectively, are supplied with liquid. The pump then' being started the liquid in the suction chamber and the conduit 34 is discharged into the conduit 35 and the discharge chamber, thus depleting the conduit 34 and the suction chamber. Immediately the liquid has reached the discharge side of the pump the priming action has started. The pressure then being greater on the discharge side than on the suction side of the pump, the liquid flows through the spaces of the impeller vanes at the seal 33 and back into the suction conduit 34, as indicated by inclined arrows and the curved dotted lines in Fig. 6, the speed of the impeller vanes subjecting the liquid to a high .velocity. The thus returning streams of liquid impinge against the opposing inclined wall 31 minal b of the wall an ejector effect which forces the air from the suction side of the pump, which air entrained with the liquid is forced into the discharge conduit 35. The air being lighter than the liquid leaves at the top of the pump. The liquid returns again to the impeller vanes and back into the suction conduit' as indicated by the inclined arrows in Fig. 6.

The eflect of ejecting the air as just described produces a vacuum on the suction side of the pump, with the result that the liquid finally flows through the inlet I 5 to the suction chamber. The pump now being primed operates under its normal working condition. Once the pump is primed the recirculating liquid indicated by the inclined arrows in Fig. 6 is inappreciable as the pressures on both the suction and discharge sides of the pump are approximately the same except that the pressure on the discharge side at the seal 33 is somewhat higher than that on the suction side at such seal.

It is to be understood that my invention is not'limited to the particular construction herein disclosed to exemplify my invention, as the structure and organization may be modified within the principle of the invention and the scope of the appended claims.

I claim 1. In a pump having a rotary impeller including peripheral vanes, means providing an annular peripheral channel for the vanes and having reversely-disposed elongated passages constituting expansions of extended portions of the respective sides of said channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the vanes, the adjacent ends of said passages being in lateral communication with each other transversely of the channel, and the oppositeends of said passages constituting intalre and discharge portions, respectively.

2. In a pump having a rotary impeller including peripheral vanes, means providing'an annular peripheralchannel for the .vanes and having reversely-disposed elongated passages constituting expansions of extended portions of the respective sides of said channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the varies, the adjacent ends of said passages converging toward the channel and being in lateral communication with each other transversely of the channel, and the opposite ends of said passages constituting intake and discharge portions, respectively.

3. In a pump having a rotary'impeller including peripheral vanes, means providing an annular peripheral channel for the vanes, which channel is interrupted by a sealing projection concentric with and in close relation to the outer ends of the vanes, andproviding also reverselydisposed elongated passages constituting expansions of extended portions of the respective sides of said channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the vanes, the adjacent ends of said passages being in proximity to the said sealing projection and being in lateral communication with each other transversely of the channel, and the opposite ends of said passages constituting. intake and discharge portions, respectively. I

4. In a pump having a rotary impeller including peripheral vanes, a circular structure within which said impeller is mounted, comp ising a pair of discal walls and a spacer ring interposed therebetween adjacent the periphery of the structure to provide a continuous annular peripheral channel for the impeller vanes, there being provided in the respective walls reversely-disposed elongated passages constituting expansions of extended portions of the respective sides of the annular channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the vanes, the adjacent ends of said passages being in lateral communication with each other transversely of the channel, and the opposite ends of said passages constituting intake and discharge portions, respectively.

5. A pump comprising a casing, 'walls partitioning the interior of the casing into two chambers, a fluidinlet for one chamber, a fluid outlet for the other chamber, and an impeller, in-

cluding peripheral vanes, mounted to rotate between said walls, there being provided between the walls an annular peripheral, channel for the impeller vanes, and in the respective walls reversely-disposed elongated passages constituting expansions of extended portions of the respective sides of the annular channel, the sides of said channel opposite to the respective expanded side portions thereof being, in close relation to the path of the vanes, the adjacent ends of said passages being in lateral communication with each other transversely of the channel, and the opposite ends of said passages opening into the respective chambers.

6. A pump comprising a casing, walls partitioning the interior of the easing into two chambers, a fluid inlet for one. chamber, a fluid outlet for the other chamber, and an impeller, including peripheral vanes; mounted to rotate between said walls, there being provided between the walls an annular peripheral channel for the impeller vanes, and in the respective walls reversely-disposed elongated passages constituting expansions of extended portions of the respective sides of the annular channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the vanes, the adjacent ends of said passages being constricted and in lateral communication with each other transversely of .the channel, and the opposite ends of said passages opening into the respective chambers.

7. A pump comprising a casing, walls partitioning the interior of the casing into two chambers, a. fluid inlet for one chamber, a fluid outlet for the other chamber, and an impeller, in-

cluding peripheral vanes, mounted to rotate between said walls, there being provided between the walls an annular peripheral channel for the impeller vanes, which channel is interrupted by a sealing projection concentric with and in close relation to the'outer ends of the vanes, and there being provided in the respective walls reverselydisposed elongated passages constituting expansions of extended portions of the respective sides of theannular channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the vanes, the adjacent ends of said passages being in proximity to the said sealing projection and being in lateral communication with each other transversely of the channel, and the opposite ends of said passages opening into the respective chambers.

8. A pump comprising a casing, walls partitioning the interior of the easing into two chambers, a fluid inlet for one chamber, a fluid outlet for the other chamber, and an impeller, including peripheral vanes, mounted to rotate between said walls, there being provided between the walls an annular peripheral channel for the impeller vanes, which channel is interrupted by two spaced-apart sealing projections concentric with and in close relation to the outer ends of the vanes, and there being provided in the respective walls reversely-disposed elongated-passages constituting expansions of extended portions of the respective sides of the annular channel, the sides of said channel opposite to the respective expanded side portions thereof being in close relation to the path of the vanes, the adjacent ends of said passages being in proximity to one of said sealing projections and being in latoral communication with each other transversely of the channel, and the opposite ends of said passages opening into the respective chambers adjacent the respective ends of the other sealing projection.

RHEUEL H. FREDERICK. 

